An Issue with Normals and SubDivison
Merge by distance M&gt;B and change the threshold until you've removed enough vertices to minimize the seam.
Then add an edge loop to support the geometry in front of that area.
See the gif below for a visual:


Note that this will fix the issue for now, but in the future, you should consider better topology, and not strictly rely on booleans for modeling.
topology guides is a good resource to begin with, and there are many questions here on the site that will lead in the right direction also.